Nasal mask



FIG. 1 is a perspective view of a nasal mask showing our new design.

FIG. 2 is a front view thereof.

FIG. 3 is a rear view thereof.

FIG. 4 is a right side view thereof.

FIG. 5 is a left side view thereof.

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The broken lines in the drawings illustrate portions of the nasal maskthat form no part of the claimed design.

CLAIM The ornamental design for a nasal mask, as shown and described.